40139209 has 12 divisors (see below), whose sum is σ = 46041408. Its totient is φ = 34901240.

The previous prime is 40139207. The next prime is 40139213. The reversal of 40139209 is 90293104.

It is a happy number.

40139209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 40139209 - 2¹ = 40139207 is a prime.

It is a super-3 number, since 3×40139209³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40139201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4429 + ... + 9994.

It is an arithmetic number, because the mean of its divisors is an integer number (3836784).

Almost surely, 2^40139209 is an apocalyptic number.

It is an amenable number.

40139209 is a deficient number, since it is larger than the sum of its proper divisors (5902199).

40139209 is a wasteful number, since it uses less digits than its factorization.

40139209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14468 (or 14457 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 40139209 is about 6335.5511993827. The cubic root of 40139209 is about 342.3914700442.

The spelling of 40139209 in words is "forty million, one hundred thirty-nine thousand, two hundred nine".